The dirty little secret behind electric cars

Don't be fooled by the claims of the pro-electric car camp – our best bet for low-emissions vehicles is still natural gas

Does the car of the future really need to be electric to be environmentally responsible?

On a recent trip to Hawaii, the car service sent a beautiful Tesla to pick us up at the airport.

The driver told us how proud he was to be driving a “zero-emissions” vehicle.

This prompted me to ask him what powers the car? When he replied “electricity,” I asked how that electricity was generated. Looking at the windmills on the ridges above us, he said, “Those windmills I guess.”

I informed him that Hawaii’s hundred-plus windmills generate only five per cent of the state’s power. The other 95 per cent comes from carbon emissions-intensive diesel-fueled power plants. Then I explained that each time an energy source is changed to another form, an efficiency loss occurs. The largest loss comes when the diesel is burned in the power plant and the electricity is sent to the Tesla’s charging station. The next loss occurs when the car’s battery charger converts the AC electricity to chemical energy stored in the battery. The final loss occurs when that chemical energy is converted to DC power and delivered to the electric motors driving the wheels.

Combined, these efficiency losses consume some 75 per cent of the energy originally contained in the diesel fuel, leaving just 25 per cent to power the Tesla.

But what if that diesel fuel was burned in an internal combustion engine? The latest turbo-diesel engines approach 50 per cent thermal efficiency, so the car would use only half as much diesel and emit half the emissions.

This anecdote conveys two realities. First, electric cars are only as “green” as the fuel used to generate the electricity they consume. Second, sometimes it’s environmentally better to burn the fuel in the car than the power plant.

How does that first reality apply to electric cars in Canada? B.C., Manitoba, Quebec and Newfoundland generate the vast majority of their electricity from hydro, so it’s thumbs up for electric cars. Coal supplies most of the electricity in Alberta, Saskatchewan, Nova Scotia and P.E.I. New Brunswick’s electricity is fueled by a roughly equal mix of hydro, coal, fuel oil and natural gas. So electric cars are not green in those five provinces.

That leaves Ontario, the province that just announced a $7-billion Climate Action Plan featuring generous subsidies to promote “an electric car in every driveway.”

On the surface, the fact that some 80 per cent of Ontario’s electricity is generated by hydro and nuclear makes electric cars look green. But it’s not that simple. Those millions of new electric cars will require a massive expansion of Ontario’s power systems.

So what’s really important isn’t the current fuel mix but rather what would fuel all that new electricity. The plan makes bold assertions about expansion of wind and solar but the governing Liberals’ last grand green plan was absolutely disastrous, enriching wind and solar companies with huge subsidies while driving Ontario from one of North America’s lowest power-rate jurisdictions to one of the highest. And since the wind is unpredictable, and since Ontario’s winter daylight hours are short and summer days often cloudy, essentially all wind and solar must be backed up by reliable facilities. Billions have already been spent on back-up natural-gas-fueled power plants and many more billions would be required to power all those new electric cars.

That’s where the second reality from my Tesla anecdote applies, not just in Ontario but across the country. Even in provinces where electric cars are actually green, not everyone wants to put up with the “range anxiety” of plug-in cars.

Given that the CO2 emissions intensity of natural gas is 25 per cent lower than gasoline or diesel fuel, the emissions reduction from switching a large portion of the country’s vehicle fleet to natural gas would be dramatic. Moreover, toxic particulate and nitrogen oxide emissions are eliminated with clean-burning natural gas.

The Canadian Natural Gas Vehicle Alliance is working to accomplish this vital objective. The International Association for Natural Gas vehicles estimates that there are more than 20 million natural gas-powered vehicles already on the road.